1. Field of Invention
This invention pertains to a step apparatus for vehicles, and particularly to a step apparatus which facilitates ingress and egress from vehicles with high ground or road clearance.
2. Prior Art and Other Considerations
Numerous types of vehicles have high ground clearance, for reasons ranging from the sheer size of the vehicle to desirability of roving over rugged terrain. For example, large trucks which haul freight have truck beds which are, by necessity, considerably elevated from the ground in view of the truck size. Other types of vehicles, such as recreational vehicles (RVs), although generally midsized, are deliberately elevated to enable the vehicles to travel off-road.
In recent years recreational vehicles (RVs) and light trucks have been sold in increasing numbers. These vehicles are now being used not just for light hauling and off-road trips, but also for commuting and general transportation purposes. The drawback of having high road clearance for RVs is that embarking and disembarking the vehicle presents difficulty for certain passengers most notably the elderly, the infirm, children, and women wearing tight fitting skirts or gowns.
Previous attempts to overcome the problem of ingress and egress into vehicles having high ground clearance fall into two basic categories: permanent steps and retractable steps. The first type of step has limited effectiveness since the closer the step gets to the ground the more the vehicle road clearance is compromised.
The second type of step, the retractable step, also has certain drawbacks. An example of a retractable step is shown in U.S. Pat. No. 3,751,068 to Green, wherein the step extends down and out by a cable attached to the hinged end of a door. The Green patent does not disclose any way of adjusting the height or the number of steps. Furthermore, since the device patented by Green can only be used with vehicles which have hinged doors, it is not possible to use the device with sliding door vehicles. Finally, by attaching the cable to the hinged end of the door, the Green device has only limited energy available for extending the step since the distance of displacement of the cable is minimal.
U.S. Pat. No. 3,608,957 (Maneck) shows a horizontal running board for vehicles with sliding doors. The Maneck running board extends outwardly horizontally by the movement of the door. The Maneck device cannot be readily adapted for use with hinged doors. Maneck also does not disclose any way of adjusting the number and height of the steps.
U.S. Pat. No. 3,572,753 to Claassen shows a sole outwardly-angled arm which has an oblique orientation of approximately 45.degree. to a horizontal frame bar.
U.S. Pat. No. 4,062,582 to Youmans discloses spaced support arms which are not spaced in relation to the longitudinal horizontal axis of the vehicle.